The proposed work is a continuation of studies on the role of phospholipase A in experimental cell injury. Studies are performed on tissues from rats exposed to endotoxin shock (E. coli endotoxin). Assays for phospholipid content will be performed on whole homogenates and specific subcellular structures of the rat liver and kidney. The rate of formation of lysophosphatides (as an indication of phospholipase A activity) will be measured in vivo and in vitro under control conditions and following treatment of the animals or their tissues with the bacterial endotoxin. One overall objective of this proposal is to gain insight into the biochemical mechanisms and specific locations of cell injury caused by endotoxin shock.